1. Field of the Invention
The present invention relates to a substrate processing method and a substrate processing apparatus for removing, by using a removal liquid, an organic matter on a substrate or a reaction product generated on the surface of a substrate on which a thin film formed is patterned by dry etching by using a resist film as a mask.
The invention also relates to a substrate processing apparatus for drying a substrate processed with de-ionized water and, more particularly, to a substrate processing apparatus for supplying a removal liquid for removing an organic matter on a substrate or a reaction product generated on a substrate on which a thin film formed is patterned by dry etching by using a resist film as a mask, further supplying de-ionized water to the substrate, and drying the substrate.
2. Description of the Background Art
Processes of manufacturing a semiconductor device include a process of forming interconnections of a semiconductor device by etching a thin film made of a metal such as aluminum or copper (metal film) formed on a substrate such as a semiconductor wafer by using a patterned resist film as a mask.
The etching process is executed by, for example, dry etching such as RIE (Reactive Ion Etching).
Since the power of reactive ions used for such dry etching is extremely strong, on completion of the etching on the metal film, the resist film also changes at a predetermined rate, a part of the resist film is converted to a reaction product such as a polymer, and the reaction product is deposited on side walls of the metal film. Since the reaction product is not removed by a following resist removing process, before or after executing the resist removing process, the reaction product has to be removed.
Conventionally, a reaction product removing process is therefore performed in such a manner that a reaction product deposited on the side walls of a metal film is removed by supplying a removal liquid having an action of removing the reaction production to the substrate after the dry etching process or resist removing process, after that, the substrate is cleaned with de-ionized water and, further, the de-ionized water is drained off so as to dry the substrate.
As a pattern is becoming finer in recent years, however, there is a case that de-ionized water on a substrate cannot be sufficiently removed only by the draining operation for drying. If de-ionized water remains on the substrate, it is feared that the remained de-ionized water reacts with a thin film, a component in the air, or a contaminant in the air and another contaminant is generated.
Therefore, when there is a process of supplying de-ionized water to a substrate, the substrate has to be dried with reliability.
Particularly, in the case where de-ionized water remains on a wafer W from which a reaction product has been removed, since a metal thin film is often formed on the surface of the substrate, a problem such that the metal reacts with de-ionized water in the air and an unnecessary oxide is generated arises. When the substrate is carried to a process performed under a vacuum condition such as CVD, the de-ionized water remained on the substrate exerts an adverse influence on the process.
Further, in association with reduction in size of a pattern, a change in pretreatment, and the like in recent years, the nature of a reaction product varies, and a problem such that longer time is required to remove the reaction production in the conventional reaction production removing process arises. Consequently, in recent years, a removal liquid having improved performance of removing a reaction product by being used at temperature higher than ordinary temperature has been developed. Even in the case of using such a removal liquid, there is a case that long time is required to remove a reaction product.
The present invention is directed to a substrate processing apparatus for removing an organic matter adhered on a substrate by a removal liquid of the organic matter.
According to the present invention, a substrate processing apparatus for removing an organic matter adhered to a substrate by a removal liquid of the organic matter, comprises: a rotary holding unit for holding the substrate so as to be rotatable; a removal liquid supplying mechanism for supplying the removal liquid toward a surface of the substrate held by the rotary holding unit; a de-ionized water supplying mechanism for supplying de-ionized water toward the surface of the substrate held by the rotary holding unit; and a heating unit for heating the substrate.
In this substrate processing apparatus, after a process of removing a reaction product, a substrate can be dried with reliability. Consequently, occurrence of a problem such that de-ionized water remains on a metal pattern on the substrate from which the reaction product has been removed and an oxide is generated, and occurrence of a problem such that when a substrate from which a reaction product has been removed is carried to a process performed under a vacuum condition, de-ionized water attached to the substrate exerts an adverse influence on the process can be effectively prevented.
Preferably, in the substrate processing apparatus, the heating unit heats the substrate before the removal liquid is supplied to the substrate by the removal liquid supplying mechanism.
In this substrate processing apparatus, decrease in the temperature of the removal liquid supplied to the substrate is prevented and the process of removing a reaction product can be completed in short time.
According to another aspect of the present invention, a substrate processing apparatus for removing an organic matter adhered to a substrate by a removal liquid of the organic matter, comprises: a substrate holding unit for holding the substrate; a removal liquid supplying mechanism for supplying the removal liquid toward the substrate held by the substrate holding unit; a de-ionized water supplying mechanism for supplying de-ionized water toward the substrate held by the substrate holding unit; a chamber for housing the substrate held by the substrate holding unit; and a pressure reducing unit for reducing pressure in the chamber.
In this substrate processing apparatus, the substrate can be dried with reliability.
According to still another aspect of the present invention, a substrate processing apparatus for removing an organic matter adhered to a substrate by a removal liquid of the organic matter, comprises: a substrate holding unit for holding the substrate; a removal liquid supplying mechanism for supplying the removal liquid toward the substrate held by the substrate holding unit; a de-ionized water supplying mechanism for supplying de-ionized water toward the substrate held by the substrate holding unit; a chamber for housing the substrate; a transporting unit for transporting the substrate held by the substrate holding unit to the chamber; and a pressure reducing unit for reducing pressure in the chamber.
In this substrate processing apparatus, the substrate can be dried with reliability.
An object of the invention is therefore to completely dry a substrate from which an organic matter has been removed by a removal liquid of the organic matter.
These and other objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.